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  4. Case Studies

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- [Voiceover] Case Study Number One, I've got two case studies. This first case study looks, it's a case study coming from the Permian and it comes straight out of the Delaware Basin, the Avalon Shale, and what's happened here is that an operator, a small operator, called us to look at their inventory and help them high grade their inventory because they want to drill under those, what are best wells, right now. So, what we did was place those wells within the geological setting, sequence the geographic setting properly, go ahead and then, find the Type Curve that matches that setting, go and look at the well that the Type Curve came from, we'll go to that well and then, we'll look at the source, at the stimulated rock volume around the well. That's what you see here, the stimulated rock volume. It allows us to go on and predict the static properties that give rise to that performance. That's what they used to allow them to high grade the wells. I want to take a closer look, we're going to take a closer look at this one situation and see what happens. Here's a plot of the permeability in nanodarcys and then the fraction of this, of the rock, was in this carbonate, from the plug analysis. And, what this has done for us, it allows us to be able to decide, to make some judgement. In this basin, it's known in these parts that the less carbonate you have, the better the reservoir. The more muds you have, the better the reservoir. So, first off, the carbonate content increases, GRI, we'll put a threshold there. Then, we'll go on to look at the permeability. The higher the permeability, the more likely the rock would allow fuel to go in, so the hydraulic frack will be more successful if it can get past, get through, into a lot of pore throats. So, that's what you see here. This allows us to high grade this reservoir and high grade the prospects. And, the results show that three wells drilled on the basis of this, six month results, show the good performance. It all improved. This other case here, it's a case, a very rare case where you get to use your Geo model really early in the process. Entering a new basin is always something that gets a lot of people concerned and this is a case where an operator was about to enter a deep well of a Pre-Salt basin, offshore, West Africa. Now, the good thing here is that, already, Tupi had been drilled in Brazil, the Well Tupi One which was a very huge success, so there was both evidence from the regional analogs to show that there is opportunity here. Also, a lot of work in Namibia, outcrops in Namibia and outcrops in Angola had all shown that you have similar rock patterns across both sides of the South Atlantic. And so, the goal for us was, before the well is drilled, we had a request, "Can you help, in the local area around the well, "can you help high grade the quality "so we can optimize our well location?" And, we went in there, after looking at all of the information about the distribution of facies in that basin because the rock quality actually does have a facies conduit constraint in there. We identified that two things were very important. the local topography would control the ability of microorganisms or microbialites to be formed at any location in the basin. And, also, we were able to figure that if we were able to now have the basin geometry at the time of the position and, also, the source, the sediment source direction at the time of the position, these two properties, we could use them together to help us decide a location of the facies that were common and typical in that type of setting. So we did that, and here you have a schematic that shows some of the theoretical background. That study done by Johnson and Grotzinger in 2006 had shown clearly that you'd have more growth of microbialites as you move away from areas where you had a lot of sediment input. So, we went ahead and used information along with some seismic to build some property models and those property models allowed us to predict the quality distribution of Syn-rift facies in this basin, deep water basin. And, you can see here, these two wells were drilled, they'd been drilled a long time. The most recent one of these wells were drilled in 2014, it is the Bicuar-1 and you can look up information on that, online. Both wells turned out to be a success, way more than we even thought they were gonna be, but these are different ways you can apply Geo. It's not all restricted to what you do in late field life or after everyone else had done some exploration work. There is value at any point in time because it's just a tool. Here's an example of deep water Eolian Reservoir, Gulf of Mexico, and I only gonna show the geology part. So, there are four main criteria that were important because you are talking about dunes here and dune sets as they look when they are preserved. So, these four criteria were varied and those are the schematics that I showed you how these four criteria were varied all across the model. The key things to note is that sand dunes, when they get preserved, they're preserved as individual objects and that object shows a variation in rock properties and that was what we were supposed to capture. So, here you have a model that I built then, and what it does is that it captures that variation, captures that variation. Let's take a close-up look here and see one of those. So, we'll see a close-up of one of those dunes sets that have been preserved shows you the variation of rock properties. It shows that variation from axis to the margins of each one of these dune sets. So, in conclusion, models are really useful. You can use them to study. You can use them to plan. You can use them to design things like completions. You can use them to predict performance. And, the best part of it is that it actually is the least-priced or the one activity in the subsurface that costs the least and it gives you so much valuable information.